Vacuum seal, method and apparatus



Aug. 10 1926. 1,595,240 Y O. MINTON VACUUM SEAL, METHOD AND APPARATUS 07A {NVEN'TOR ATTORNEY Aug. 1o 1926. ,"95,24o

O. MINTON VACUUM SEAL, METHOD AND APPARATUS Filed June 20. 1925 4 Sheets-Sheet 2 A fg-z- N A A /7 Z0 ZI 4?' 87 32 43 Z4 67; 5a 32 44 w 45 55 46 J= 57 87 -m 55 I5 1 5! `INVENTOR l BY ZL( ATTORNEY Aug. 10 1926.

O. MINTON VACUUM SEAL, METHOD AND APPARATUS 4 Sheets-'Sheet 5 Filed June 20, 1923 5 4 4% m z :1 W 5 a 4 4 z u 1 a\\ 4 0l oO 7l /l 6 oo o/o. 0 /0 mm 4 Y n w u. m n 75 T/ A V w .a a hwk w w 5 t INVENTOR BY Q4 ATTORNEY Aug. 10 1926. 1,595,240

O. MINTON VACUUM SEAL, METHOD AND APPARATUS Filed June 20. 1925 4 Sheets-Sheet 4 0 l. o Q l\ @n 'KQ l l f m J, RIG

L\ m D' n n mi? s Il) l l I Q N INVENTOR UNITED STATES PATENT OFFICE.-

OGDEN IINTON, OF GCH, mmm.

VACUUI SEAL, IBTHOD m APPARATUS.

pplieltion lell Ille M, 1823. Serial In. mm.

My invention relates to the method of treatin;r materials in a vacuum, and more particularly to the method of protecting the opening or openings into the vacuum chamber, through which opening or openings the material to be treated is introduced and withdrawn from the chamber.

More particularly it relates tosealing the entrance and exit passages of the vacuum chamber by a plurality of rotating contacting members forming between thema'dry rotating air-tight closure, andsealing other portions of the surfaces fof the rotating members by means of liquid seals.

" treated in the vacuum chambe My invention further relates to passing the web of paper, or other material to be treated into the vacuum chamber, through the rotating dry air-tight closure Without the aid of belts.

My invention further relates to sealing said rotating members with liquid seals, the liquid not'coming in contact with the unguarded or unprotected web of paper, or other similar material, to be dried or other- Wise treated in the vacuum chamber.

justable passage in contact with a portion of a rotating member and then removing the liquid, forming said tilm, from the rotating member before that portion of the rotating member again comes in contact with the web of paper, or similar material, to be My invention further relates to a closure for a vacuum chamber consisting of a pluprality of rotating members sealing the inlet and exit passages to said chamber, at least one of each set of rolling contact members being provided with a yielding periphery to come in direct contact with, and press the material to be treated, firmly against one of the other rolls to form a dry rolling air-tight closure, and then sealing other portions of the rolls by means of a liquid seal.

My invention further relates to one form of apparatus, to carry out my improved method. in which the periphery of one or more of the rotating rolls is rendered airtight by means of a liquid seal, and the ends of said roll or rolls are rendered airtight by packing means; or, preferably, by another liquid seal to form a film .of liquid, preferably a lubricant, between the ends of said roll or rolls and a fixed non-rotating part of the vacuum apparatus.

The liquid which I preferably employ to seal the periphery of the roll or rolls is water, or liquid When a liquid is used to seal the end of the roll or rolls, water or a similar liquid may be used, but preferably'I employ some lubricating oil to form a lubricating film between the rotating and stationary parts so as to reduce friction, as my device is meant to be used at high speeds where a lubricant would he necessary. It is understood, however, that my invention may be used at either or low speeds.

My invention further relates to the method of drying any sheet material in a vacnum chamber, Whether` such material be woven fabric or not. It relates more particularly to drying a continuous web of paper either coming from the wet end of a paper machine, or from a sizing vat, or from a coloring apparatus, coating machine or printing machine or directly from a roll of "wet paper.

hy invention further relates to certain :steps and combination of steps, also to certain elements and combinations of elements, whereby the method or processes herein described may be carried out, as well as to certain details of construction, all of which will be more fully hereinafter described in the specification and claims. Y

Various forms of apparatus may be employed to carry out my improved method,

I have shown in the accompanying drawings one form of apparatus which may be pointed ont in the h so used; but it is to be distinctly understood N that this orm is shown simply by way of example vand that myinvention is not to be confined to it.

In the accompanying drawings the same reference numerals refer to similar parts in the several figures.

' Fig. 1 is a vertical section through a vacnum drying apparatus, which is shown somewhat diagrammatically, the entrance and exit pamages of the vacuum chamber being protected by my improved vacuum seals which are shown in side elevation;

Fig. 2 is avertical section on an enlarged scale of my vacuum seal protecting the entrance of the vacuum chamber;

Fig. 3 is a vertical section of my vacuum seal protecting the exit passage of the vacuum chamber;

Fig. 4 is a detail vertical section substantially on the line 4 4 of Fig. 3;

Fig. 5 is a detail section;

Fig. 6 is a vertical section on the staggered section line 6 6 of Fig. 2, showing the manner of mounting the rotating rolls.

The vacuum chamber A, Fig. 1, may be of any suitable construction and provided with drying drums or cylinders 1,2, 3, 4 and 5. The drying drums or cylinders are steam heated (not shown) in the Well known manner in the art and each drying drum or cylinder is provided with a separate felt 6 rlmning over guide rolls 7, These separate felts 6, 6 may be dried in any suitable manner, such as by passing adjacent to, or in contact with, steam radiators 8, 8, to which steam is supplied by the pipe 9, one of these steam radiators being preferably mounted between two of the separate felts 6, 6 and serving to dry both felts. The entrance B to the vacuum chamber A. is protected by one of my seals; the exit paage C is protected by a similar seal, a little differently arranged, but the same in all essential particulars.

The vacuum is maintained in the vacuum chamber A in any suitable manner, such as by connecting pipe 10 with any suitable form of vacuum apparatus or condenser. In some cases, to prevent condensation of Water upon the top 11 of the vacuum chamber, I may heat the top 11 in any suitable manner, as by passing steam or hot- Water through the pipes 12, 12 into the transverse chambers 13, 13 and ont through the pipes l-i. 14. This will prevent any moisture condensing on the top of the vacuum chamber and dropping onto the drying drums or cylinders 2 and 4, or upon the upper felts 6, 6 running in contact with these drying drums or cylinders.

ln the preferred form of apparatus, carrying out my method I preferably employ three rolls to guard and seal each passage into and out of the vacuum A.. making, in this form of apparatus, six rolls in all. In each group, or set of three rolls, two of them, 15 and 16. Fig. 2, and 5E) and 60, Fig. 3. are rolls provided preferably with a brass periphery 17. 17. The body of these rolls is preferably iron and on their ends are mounted steel bearing shafts 1S, 18 and 62 and 63. The rolls 19 and 6l are preferably formed of iron and are provided with a yielding periphery 20, preferably rubber, and rest upon the other rolls 15 and 16 and 59 and 60, as shown respectively in Figs. 2 and 3. This rubber periphery 20 may be secured to the roll 19 in any suitable manner, such as by being vulcanized on the rolls. These rolls 19 and 61 are also provided with steel bearing shafts 21, 64 secured to them in any suitable manner.

At the point 22, Where thel rubber roll 19 rests upon the brass roll 15, there will be a dry air-tight rolling closure. and a similar dry air-tight rolling closure at polnt 23 Where the rubber roll 19 rests upon the brass roll 16.

To make the periphery of the brass rolls 15 and 16 air-tight, with relation lo the frame 24 of the seal, which frame is secured to, and is practically a part of, the vacuum apparatus A. I employ a liquid seal 25, Fig. 2. This liquid is preferably water, or an)v other similar material, and is fed through the supply pipe 26 into the chamber 27, surplus water falling over the Weir 2S into the Well 2S), where it is drawn oft b v means of the Waste pipe 30. Free passage of the liquid 25, as for example, Water, into the vacuum chamber is prevented by an adjustable wiper or packing 100. This u'iper or packing is formed 0f a contact member 31 (see Fig. 5 for construction) bearing against the brass roll 16 and forming a restricted paage 32. This member 31 is adjustable so that the area of the restricted passage 32 is also adjustable depending upon the degree of pressure with which the member 3l is pressed against the periphery of the brass roll 16.

This member 31 is preferably formed of rubber and has a surface 33 lo [it into the Haring opening 31 in the frame 24. Mount ed within the` rubber member 31 is a pneumatic inflatable tube 35. and a metal adjustable member 36 within which lits the end of the bolt 3T provided with a nut 3S. In positioning the parts the rubber member 31, the pneumatic tube and the metal member 36 are placed in the flaring opening 3l and the rubber member is locken io rnc Trume 24: by rotating the nut. 3S. This will cause the conical metal member 36.10 more down the inclined surface of the rubber member 3l and lock it firmly in the socket fl-l. Air under pressure is forced into the pneumatic tube thereby pressing the portion 39 of the rubber member 31 into contact with lhe brass roll 16. This pneumatic pref'sure upon the end 39 of the rubber member 31 serves to regulate the area of the restricted passage and consequently the amount of liquid 25 which will pass into the Well 40 which is connected with the vacuum maintained in the vacuum chamber A. The liquid which passes through the restricted passage 32 falls into this well 40 and is I may use other types A of the member 31 to form a restricted passage.

The member 31 may be so firmly pressed against the roll 16 as to permit hardly any liquid to pass through the restricted passage 32. Preferably, however, the pressure within the tube 35 is so regulated that only a small quantity of water will pass through the restricted passage 32 in the form of a film adhering to the periphery of the roll 16. This film of water serves as a seal against the admission of air to the vacuum chamber, and also as a lubricant, in that it prevents excessive wear of the surface 39 of the rubber `member 3l against .the roll. I

may'fin some cases use only the member 31, both as a seal and Wiper. That is, the film of water is so small as not to be objectionable.

Before this film of water on the brass roll 16 could be transferred to the rubber roll 19, and by it transferred to the web of pae per or other similar material 42 to be' treated, I substantially remove the ilmof liquid from the roll 16. This may be done in various ways. I have shown in Fig. 2 a pneumatic wiper 43 consisting preferably of a strip of flexible material 44 held at its longitudinal edges by means of the fastening devices 45 and passing over a flexible pneumatic tube 46. Pneumatic pressure within this tube 46 will press the material 44, withany desired pressure,-

against the periphery of the roll 16 neces sary to remove the excess liquid which may adhere to the periphery of said roll. In some casesI may use a second pneumatic wiper 49, which is similar in all respects to the wiper 100, shown in Fig. 5, except the parts are so adjusted as to remove any surplus moisture which may pass the first wiper 43. The wiper 100 is preferably adjusted, as previously stated, to form a very small restricted passage 32 to permit a thin film of liquid to pass between it and the roll. The wiper 49 is adjusted to remove any film of liquid, which may not beremoved by the wiper 43.

In connection with the cooperating brass roll 15 I use duplicate restricted passages and wipers but they have to be arranged in a little different manner; their function,"

however, is the same.

The brass roll 15 revolves in dcontact with the liquid seal 50 of water, or similar liquid,

which is fed into the receptacle 51 through the water inlet 52 and passes through the restricted passage 32 formed by the wiper 100 and between the end 39 of the rubber 31 of said wiper, and the brass roll 15. The action of this device is the same in all respects as of packing in place the one previously described in connection with the roll 16. The liquid of the seal will pass through the restricted passage 32 and will be caught in the portion 53 of the receptacle 51. Any excess liquid williiow into the overflow waste pipe 54. Since the roll 15 revolves clockwise and in contact with the liquid of the seal some of the liquid will adhere to its surface. This is removed by a wiper 43', which is the same in all respects as the wiper 43 previously described. That portion of the liquid seal lying to the right of the restricted passage 32, Fig. 2, will be under the vacuum maintained in the vacuum chamber A, while that portion of the liquid seal to the left of the restricted passage 32 will be under atmospheric pressure, the restricted passage 32 being the dividing line between the vacuum and the atmospheric pressures.

Should any moisture remain upon the brass roll 15 after it passes the wiper 43, it may be removed by the wiper 49', which is .the same in all respects as the wiper 49 operating in connection with the roll 16. It may be, however, adjusted closer to the brass roll to substantially remove any moisture from the roll, rather than to form a restructed passage and permit a thin film of liquid to pass between it and the roll.

To guard against splash or spray of water being carried into the machine proper. I preferably mount a strip of felt, or other similar material 56 on the edge 55 of the receptacle 51, the felt 56 being partly supported by a shelf or bracket 57. In some cases I may also employ aV guard 58, as shown in Fig. 2.

The exit passage C in the vacuum chamber A is protected by a. similar set of rolls and liquid seals.

In this set the rolls (Fig. 59 and 60 are the brass rolls and 6l is the rubber roll. The restricted passage 32 and the wipers 43 and 49 are the saule, as previously described except that they are necessarily located a little differently from their prototypes located at the inlet- B of the vacuum chamber A.

I can seal the ends of the different sets of rolls by packing means alone. Preferably, however. I seal the ends by another liquid seal, which is simply a thin film of liquid, preferably, a lubricant as my device may be run at high speeds.

I' have shown the roll 16, Fig. 6, supported by means of a. roller bearing 65 (only a metal ring 71 which bears directly upon the smooth lubricated Surfaces 67 and 68 of the face plate 66. Between the metal sealing ring 71 and the end of the roll 16, I mount a. resilient member, as for example, a ring of rubber 72, to yieldingly press the metal sealing ring 71 against the stationary surfaces 67 and 68 on the face plate 66. This metal ring 71 is supported directly upon an annular ring 73 which, in turn. is secured to the end of the brass roller 16 by means of the bolts 74, 74.

The metal ring is keyed to the annular supporting ring 73 by the key 171.

The nuts 75. 75 are used to clamp the rubber ring 72 in place and hold it true. This construction is. of course.l duplicated 0n the other end of the roller 16 and on both ends of the roller 15.

The roller 19, which has preferably an iron core and a rubber covering 20. is provided on its end with a sealing ring 76 L-shaped in cross section. The side 77 of this ring bears uponthe smooth lubricated surfaces 68, 69 of the face plate 66. The other portion 78 of ring 76 rests upon the metal sealing rings 71, 71 carried b v the brass rolls 15 and 16. (Only one sealing ring 71 being shown in Fig. 6). The resilience of the rubber periphery 26 0f the roll 19 is sufficient to press the metal sealing ring 76 firmly against the contact surfaces 68 and 69 of the face plate 66. These metal rings 76 and 71 bear against the face plate 66 so as to form an air-tight fit and prevent any air working aronndthe ends of the rolls. Both ends of the rubber roll 19 are equipped with these metal friction rings 76, the other simply being a duplicate of the one shown.

The liquid used for lubricating these surfaces forms a thin film of liquid which may be termed a second liquid seal preventing air working around the ends of the rollers into the vacuum chamber A.

Any suitable liquid may be employed to form this second seal. 'hile it. would be possible to lubrieate these surfaces with a thin film of water. l preferably lubrieate them With some suitable lubricating oil or grease fed from the oil cup 780, Fig. 6. through the pipe 79 to these contacting surfaces; the oil forms a thin sealing fihn. which not only lubricates the friction rings 7l and 76` and the friction surfaces 67. 68 and 69 on the face plate 66. but also prcvents any air working by the ends of the rollers. as previously noted. Vater, it used as a lubricant. may be fed from the cup 78, or fed in any other manner to these contacting surfaces.

The brass rollers 59 and 60. Fig. 3. and the rubber roll 61 are provided with the same sealing means shown in Fig. 6. just described.

In the operation of my invention a wet web of paper 42, or any other material to be treated within the vacuum chamber, is fed into the entrance B of the vacuumchamber A by being brought into direct contact With the brass roll 15 and the rubber roll 19, Figs. 1 and 2. The rubber roll 19 presses the web 42 firmly against the brass roll 15 and thereby forms an air-tight rolling seal. The web 42 then passes down into the entrance B of the vacuum chamber A, Fig. l, in contact with the guide roll 80, around the drying drum or cylinder 1, pressed thereon by the separate felt 6. thence around the drying drums or cylinders 2. 3, 4 and 5 in contact with the separate felts 6. 6. over guide roll 81, and out through the exit passage C through the rolling dry air-tight closure between the rotating brass roll 59 and the rubber roll 61, Figs. 1 and 3.

I may employ any suitable form of doctors 82, 82. At the exit C I may use a guard 83 and a deflector plate 84 to keep the web from coming in Contact with the roller 60.

In the particular form of devices that I have illustrated the rubber roll 19 rests upon and is wholly or partially supported by the brass rolls 15 and 16. r1`hese rolls as shown in Fig. 6 are supported by the face plate 66. At times it is desirable to remove the face plate 66 for inspection or cleaning of the mechanism which would leave the ends of the rolls unsupported. I, therefore, employ a plurality of screw jacks 87. which are shown in detail in Fig. 4. These screw jacks are mounted in screw-threaded sleeves 85 mounted in bosses 86 in the fralne 24. The ends of these screw jacks are provided with recesses 88 for the reception of any suitabley tool or key to screw and nnserew the screw jack within the sleeve S5. As shown in full lilies in Fig. 4 the screw jacks are shown screwed away from the roll, as for example 69. which it is adapted to support. Preferably. I employ two of these screw jacks 87 arranged at. an angle to each other to sup` port one of the heavy brass rolls. Before the face plate is removed. the screw jacks are screwed into the dotted position shown in Fig. 4 and hold the rolls free of the face plate 66 which can then be removed. After the face plate 66 has been repositioned, the screw jacks 87 are screwed away froln the rolls and brought back into the position shown in full lines in Fig. 4. Figs. 2 and 3. The pipe plugs 89 are then screwed into place to close tbe openings as shown in Fig. 4.

My invention is particularly adapted to be used in connection with drying sheet materials in the form of papel'. though it is to be distinctly understood that it is equally applicable to and covers drying sheet material in the form of textile fabrics, as for example, drying such fabrics after they have t.ages,audyetitisusedtodayandhasbeenV inuseformanyyrs Iuthismethodthe wet paper is taken from the paper machine, cut into sheets, hung on poles, rried to the room where it is subjeded to hot air at about 13) F. for about 48 hours, and when dry, each sheet is separately calendered. Although the advantage vot drying at a comparatively low tranpcrature, whereby the moisture is slowlyevaporated, loft is obviously very inedicient and costly, -beeause it many separate manipulations, is extremely slow,-

uses extenslve door space and wasesheat.

d pa r machine in common psc., is likewlse su ject to many disdvantages. In such machines, the wet paper as it vcornes from the machine, is pamedpver many revolving cylinders, heated internally hy steam to sulliciently high degree of heat, to raise the temperature of the water in the paper to 212 F., or thereabouts.V It is customary to supply the drying cylinders with steam at approximately 5.3 pounds gauge pressure, at which the steam has a .temperature of 228 F., giving a difference of temperatul'e (228-2l2) of only 16 F. Writh` this slight difference olf temperature the transfer of heat is extremely slow, and hence it is necessary to employ many cylinders, in hoard machines often one hundred, and in news print machines, forty 'or more. l

Also due to convection and conduction lowes` as well as those incident tolealrs in the piping system and other ineiliciencies, the heat actually required for atmospheric drying of a ton of wet paper, is very :much in excess of the theoretical requirement. The thermal eiciency of atmospheric drying;r by steam heated cylinders is therefore very low. V.l'lurthermore, vthe steam roduccd from hoilingthc water out of the pagper, is driven oli into the operating mom, *and although fans and exhausters are employed, at large expense for power and Y maintenance, the room atmosphere `is so constantly saturated with moisture as to rust and ultimately destroy all, iron and steel materials, and produces an exceedingly disagreeable and unhealthy atmosphere in which to work. It is well known that the minimum temperature 212, the :atarnospherie boiling point of water, is positively inyurlous to, and vresults in oxidizing, the libres o the paper, the strength of which 1s vastly improved when the pa r is dried at lower temperatures, as in lo t drying. This atmospheric rocess requires large initial cost for cylm ers, felts, and other neceary equipment, and extensive floor s ace, and results in the consumption of linge amounts of power, and great cost for operation, maintenance and repairs.

Some of the modern open air dryers are equipped with a blower system by which an', either heated or not, is blownthrough the dryer section, which will lower the temperature at which the water is evaporated from the paper much below 212 F. 'and may, in-somecases, reduce the temperature of evaporation as lowV as^1810 F. or lower.

In my improzved 'vacuum drying method I contemplate maintaining within the chamber a vacuum of 'about 28 of mercury, in yrhich water boils at 100 F., and supplyingthe drying cylinders with steam at,5.3

pounds gauge preure producin a tem- The process which is employedl in the V,or-i g perature of 228 F. Thetemperature difference between the temperature' of the steam in the cylinders and ,that of the paper, is therefore, 128 F. in my vacuum method, or 8 times greater (16 F. 8=128 than the temperature difference in atmospheric drying as usally practiced. In my lmproved method the paper dries approximately 8 times faster than in atmosphericdrying, and I require only about one-eighth the number of drying -cylinders to dry paper at the same rate of speed. I am able to dry paper with cylinders in the same time required of 40 cylinders drying at atmospheric pressure, resulting in great economies in cost of the machine, door space and of necessary piping, felts, auxiliary equipment, and particularly in power and maintenance charges. Y

The thermal eiciency of my vacuum method is very much greater than that of the atmospheric cylinder drying heretofore in universal use for drying paper. Theoretically, it requires about 4287 pounds of steam to dry one ton of paper at atmospheric pressure, but to compensate for con- --vection andconduction losses, and those due to leaks in the piping system, and other ineiciencies, it has been shown in practice that about 10,600 pounds are required.

In my method, usingr a vacuum of about 28", the convection, conduction and piping losses are exceedingly small and the total steam required to dry a ton of paper by my method is approximately 5200 pounds.

Itis an established fact that paper dried Lis steam in the driers is at 228 F. When paper is dried by my method, therefore, a cheaper furnish or stock can be used and still produce a paper equal in strength to atmospheric dried paper, in which a higher grade furnish or stock is used. In making newsprint paper, I am able to dispense with a considerable portion of the more expensive sulphite pulp, as this can be replaced with the cheaper ground Wood pulp. By my method l also reduce the number of breaks in the web as it passes over the cylinders.

Furthermore, in my method there is a great saving of heat (or steam) because the process is carried on in a vacuum chamber which acts on the principle of a thermos bottle, and the steam and vapors driven out of the wet paper are caught in the closed vacuum chamber, and conducted away to the condenser. The operating room is free from steam, lunnidity and heat, and fans, and exhausters are dispensed with. ln the use of my method the apparatus is at all times operating under definite humidity, the control of the dryingr can be closely standardized, and the moisture content in the paper carefully regulated.

Having pointed out the many advantages of my method and apparatus over those heretofore used, it will be apparent that the use of my invention results in great economy in the initial cost of apparatus and in large savings in lcost of operation, maintenance and repairs.

Having thus described this invention in connection with one illustrative embodiment thereof, to the details of which I do not desire to be limited, what is claimed as new and what is desired to secure by Letters Patent is set forth in the appended claims.

What I claim is 1. The method of sealing an opening in a vacuum chamber against the admission of air which consists in causing members to move in intimate contact with each other and in sliding engagement with the walls of said chamber and maintaining a liquid in contact with the surfaces of some of said members and the walls of the vacuum chamber with which said surfaces contact and creating and maintaining a vacuum in the vacuum chamber.

2. The method of .sealing an opening in a Vacuum chamber against the admission of air which consists in causing members t0 move in intimate contact with each other and in slidingr engagen'ient with the walls of said chamber and maintaining water in contact with the surfaces of some of said members and the Walls of the vacuum chamber with which said surfaces contact and creating and maintaining .a vacuum in the the vacuum chamber.

3. The method of sealing an opening in a vacuum chamber against the admission of air which consists in causing rotatable members to revolve in intimate contact with each other and in sliding engagement with the walls of said chamber and maintaining a liquid in contact with the surfaces of some of said members and the walls of the vacuum chamber with which said surfaces contact and creating and maintaining a vacuum in the vacuum chamber.

4. The method of sealing an opening in a vacuum chamber against the admission of air which consists in causing rotatable members to revolve in intimate contact with cach other and in sliding engagement with the walls of said chamber and maintaining Water in contact with the surfaces of some of said members and the walls of the vacuum chamber with which said surfaces contact and creating and maintaining a vacuum in the vacuum chamber.

5. The method of sealing an opening in a vacuum chamber against the admission of air which consists in causing rotatable members to revolve in intimate contact with cach other and in sliding engagement with thc walls of said chan'ibcr, maintaining a liquid in contact with the surfaces of some of said members and the walls of the vacuum chamber with which said surfaces contact, and maintaining a liquid in contact with the end surfaces of the n'iembers and the walls of the chamber with which said end surfaces contact and creating and maintaining a vacuum in the vacuum chamber.

(3. The method of sealing an opening in a vacuum chamber against the admission of air which consists in causing rotatable members to revolve in intimate contact with each other and in sliding engagement with the walls of said chamber. maintaining a liquid in contact with the surfaces of some of said members and the walls of the vacuum chamber with which said surfaces contact, and maintaining water in contact with the end surfaces of the members and the walls of the chamber with which said end surfaces contact and creating and maintaining a vacuum in the vacuum chamber.

7- The method of sealing an opening in a vacuum chamber against the admission of air which consists in causing rotatable members to revolve in intimate Contact with each other and in sliding engagement with the walls of said chamber. maintaining a liquid in contact with the surfaces of some of said members and the walls of the vacuum chamber with which said surfaces contact, and maintaining a yielding sealing Contact between the end surfaces of said members and the walls of the chamber.

8. The method of sealing an opening in a vacuum chamber against the admission of air which consists in causing rotatable members to revolve in intimate contact with each other and m shdmg engagement with the lll() llt) IISV

walls of said chamber, maintaining said intimate contact by gravity, and maintaining a liquid in contact with the surfaces of some of said members and the walls of the.

vacuum chamber with which said surfaces contact. v

9. 'lhe method of feeding a web into and out of a vacuum chamber having entrance and exit passages which consists in passing the web into the chamber, moving the web through the chamber and out of the exit passage, excluding air from-the chamber at certain places by exerting pressure and at other-places by maintaining a liquid.

l0. The method of feeding afweb into and out of a vacuum chamber having entra'nce and exit passages which consists in passlng the web into the chamber, moving the web through the chamber and out of the exit passage, excluding air from the chamber at certain places by exerting pressure-and at other places by maintaining water.

11. The method of feeding the web into and out of a. vacuum chamber having entrance and exit passages which consists in passing the web into the chamber, moving the web through the chamber and out through thev exit passage, excluding air from the chamber at certain places by exerting pressure on the web and a moving member and at other places by maintaining a liquid in contact with other moving members and the walls of the chamber.

12. The method of feeding the web into and out of a vacuum chamber which consists in passing the web into the chamber, moving the web through the chamber and out through the exit passage, excluding air from the chamber at certain places by exerting pressure on the web and a moving member and at other places by maintaining water in contact with other moving members and the walls of the chamber.

13. The method of feeding the web into and vout of a vacuum chamber having entrance and exit passages which consists in causing rotatable members to revolve in sliding contact with the walls of said chamber and in intimate contact with each other in the openings of said chamber, passing the web between the surfaces of two of said members, and maintaining the vacuum in said chamber by maintaining a liquid in contact with the surfaces of some of said members and the Walls of the chamber with which said surfaces contact.

14C. The method of feeding a web into and out of a vacuum chamber having entrance and exit openings which consists in causing rotatable members to revolve in sliding engagement with the walls of said chamber and in intimate contact with each other in the openings of said chamber, passing the web between the surfaces of two of said members, and maintaining the vacuum in said chamber by maintainingiwater in contact with the surfaces of some of said members and the walls of the chamber with which said surfaces contact.

15. The method of feeding a web into and out of a vacuum chamber having entrance and exit openings which consists in causing rotatable membersto revolve in sliding engagement with the walls of said chamber and in intimate contact with each ,other in the openings of said chamber, passing the web between the surfaces of two of said members, and maintaining the vacuum in said chamber by maintaining a liquid in contact with the surfaces of some of said members and the walls of the chamber with which said surfaces contact, and removing substantially all of the liquid from the surfaces of Said members to prevent transference of the liquid to the web.

16. rlhe method of continuously drying any material which consists in passing the material into a vacuum chamber having entrance and exit passages, drying the material while in said chamber, moving the material through the chamber and out through the exit passage, and excluding air from the chamber at certain places by exerting presure 1nd at other places by maintaining a iqui 17. The method of continuously drying any material which consists in passing the material into a vacuum chamber having entrance and exit passages, drying the material while in said chamber, moving the material through the chamber and ont through the exit passage, and excluding air from the chamber at certain places by exerting pressure and at other places by maintaining water.

18. The method of continuously drying any web material which consists in continuousl passing the material into a vacuum cham er having entrance and exit passages, drying the material while in said chamber, moving the material through the chamber and out through the exit passage, excluding air from the chamber at certain places by exerting pressure on the web and a moving member, and at other places by maintaining a liquid inv contact with other moving mem bers and the Walls of the chamber.

19. The method of continuously drying any web material which consists in continuously passing the material Ainto a vacuum chamber having entrance and exit passages, drying the material while in said chamber, moving the material through the Chamber and out through the exit passage, excluding air from the chamber at certain places by exerting pressure on the web and a moving member, and at other places by maintaining water in contact with other moving members and the walls of the chamber.

20. The method of continuously drying any material in a. vacuum chamber having entrance and exit openings which consists in causing rotatable members to revolve in sliding engagement with the walls ot' said chamber and in intimate contact with each other in the openings of said chamber, passing the material between the surfaces oi tivo of said members, maintaining the vacuum iii said chamber by maintaining `a liquid in contact with the surfaces of some of said members and the Walls of the chamber with which said surfaces contact, and di'yiiig the material while in said chamber.

21. The method of continuouslyl drying any material in a vacuum cliaiiibei' having entrance and exit openings which consists in causing rotatable members to revolve in sliding engagement with the walls of said chamber and in intimate Contact with each other in the openings of said chamber, pasfing the material between the `surfaces of two of said members, maintaining the vacuum iii said' chamber by maintaining water iii contact with the surfaces of some ol' said members and the walls of the chamber with which said surfaces contact, and drying the material While in said chamber.

22. The method of continuously drying any Web material in a vacuum chamber having entrance and exit openings which consists in causing rotatable members to i'evolve in sliding engagement with the walls of said chamber and in intimate contact with each other in the openings of said chamber, passing the material between the surfaces of two of said members, maintaining the vacuum in said chamber by maintaining a liquid vin'contact with the surfaces of some of Said members and the Walls of the chamber with which said surfaces contact, drying the material while in said chamber, and removing substantially all of the liquid from the surfaces of said members to prevent the transference of the liquid to the web.

23. In a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, relatively moving members mounted in the passages in sliding engagement with the Walls of said chamber and in air-tight contact relatively ,to each other to partially seall said passages, and a liquid in contact With parts of the relatively moving means for further Sealing said passages and means to create and maintain a vacuum in the vacuum chamber.

24. In a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable members mounted in the passages and in airtight contact relatively to each other to seal said passages, and water sealing means in contact with parts of the relatively rotating members for further sealing said passages and means to create and maintain a vacuum in the vacuum chamber. 25. In a vacuum drying apparatus, the combination o f a vacuum chamber having entrance and exit passages, rotatable niembers mounted in the passages in sliding contact with the walls of said chamber and in air-tiglit contact relatively to each other to partially seal said passages, and a liquid in contact with parts of the relatively rotating members for further sealing said passages, one of said rotatable members having a yielding peripheral surface.

26. In a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable members mounted in the passages in sliding contact with the Walls of said chamber and iii air-tight Contact relatively to sach other to partially seal said passages, a liquid in contact with parts of the relatively rotating members for further sealing said passages. and means cooperating with one or more ol' said rotatable members adjacent the peripheral surface of said members adapted to form restricted passages for the passage of a thin lilm of liquid.

27. In a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable meinbers mounted in the passages in sliding contact with the walls of said chamber and in air-tight contact relatively to each other to partially seal said passages, a liquid in contact with parts of the relatively rotating members for further sealing said passages` means cooperating with one or more of said rotatable members adjacent the peripheral surface of said members adapted to form restricted passages for the passage of a thin film of liquid, and means to remove liquid from the surfaces of the rotatable members before the said surfaces come in contact with the material to be dried.

28. In a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable members mounted in the passages in sliding contact With the Walls of said chamber and in air-tight contact relatively to each other to partially seal said passages, a liquid in contact With parts of the relatively rotating members for further sealing said passages, means cooperating with one or more of said rotatable members adjacent the peripheral surface of said members adapted to form restricted passages for the passage of a thin film of liquid, and adjustable means to remove liquid from the surfaces of the rotatable members before the said surfaces come in contact with the material to be dried.

29. In a vacuum drying apparatus, the combination of a vacuum chamber having llO entrance and exit passages, rotatable members mounted in the passages in sliding contact with the walls of said chamber and in air-tight contact relatively to each other to partially seal said assages, a liquid in contact wit-h parts of) the relativel rotating members for further sealing sai passages, and means cooperating with one or more. of said rotatable members adjacent the peripheral surface of said members adapted to form restricted assages for the passage of a thin film of iquid, and means to remove liquid from the surfaces of the rotatable members before the said surfaces come in contact with the material to be dried, said liquid removal means consistingof a yielding material.

30. In a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable members mounted in the passages in sliding enf gagementwith the walls of said .chamber and in air-tight contact relatively to each other to partially seal said assages, a liquid in contact with parts of t e relatively rotating members for further sealing said passages, and means cooperating with one or more of said rotatable members adapted to. form restricted passages for the passage of a thin film of liquid, and means to remove lliquid from the surfaces of the rotatable members before the said surfaces come in;

Contact with the'material to be dried, said liquid removal means consisting of rubber.

31. In a vvacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable .members mounted in thevpassages in sliding en gagementwith the walls of said chamber and in 'air-ight contact relatively to each. `other to partially seal said passages, a

liquid in contact with the longitudinal-.surfaces of said rotatable members, and means for sealing the end surfaces of said rotatable members against the' admission of air. t

' 32. In a vacuum drying apparatus, thevcombination of a vacuum chamber having Ventrance and exit passages, rotatable members mounted in the passages in sliding engagement with the Walls of said chamber and in air-tight contact relatively to each other to partially ,seal said passages, a liquid in contact with the longitudinal surfacesof members against the admissionl of air. f

.33. In a vacuum vdrying apparatus,` the..V

combination ofa vacuum chamber having entrance and exit passages, rotatable mem` f bers mounted in the'passages in sliding' en'-4 in contact. with the l'longit-udmal surfaces'of said rotatable members,and'water for seal-- lentrance and exit passages,

ing the en'd surfaces of said rotatable members against the admission of air.

34. n a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable members mounted in the passages in sliding engagement with the Walls of said chamber and in air-tight contact relatively to each other to partially seal said passa es, a liquid 1n contact with parts of the r atively rotating members for further sealing said passages, and means for producing yielding engagement between the end surfaces of said rotatable members and the Walls of the entrance and exit passages.

35. The combination in a vacuum closure apparatus, avacuum chamber, one or more sea lng rolls 1n slidlng engagement with the walls of said chamber and provided with closure rings adapted to bear directly on a portion of the vacuum chamber to form an air-tight rolling connection, and yielding means to press said closure rings into contact with the vacuum chamber.

36. In a vacuum drying apparatus, the comblnation of a vacuum chamber havin entrance and exit passages, three rotatable members mounted in the passages in sliding engagement with the walls of said chamber and in air-tight contact relatively to each other, the axes of two of said members being in the same plane and the axis of the other of said members being in a different plane and a liquid in contact with the sur* faces of said members whose axes are in the same plane.

37. In a vacuum drying apparatus, the combination of a vacuum chamber having `three rotatable members mounted in the passages in sliding engagement with the walls of said chamber andin air-tight contact relatively to each other, two of said members mounted to rotate in the same plane, the other of said members. mounted above and resting by gravityupon the surfaces of the other two members and a liquid in contact with the surfaces of said members whose axes are in the same plane.

38. In a vacuum drying apparatus, the combination of a'vacuum chamber having ventrance andexit passages, three rotatable Vmembers mounted in the passages in slidsaid rotatable members, and a liquid for sealing the A-end surfaces of said rotatable r lng' engagement with the walls of said chamber and in air-tight contact relatively toeach other, two of said members being mounted to rotate in the same plane and the other ofl said members being provided with ayielding surface and mounted above and resting by gravity upon the surfaces of the lothersaid members and a liquid in Contact with. thevsurfaces of said members whose 'axesare in the same plane.

39. In a Vacuum apparatus, a vacuum chamber, two sealing rolls having a hard periphery, a third sealing roll having a yielding surface resting upon the other two rolls, metal closure rings mountedon each of the rolls provided with a hard periphery and adapted to bear directly upon and have frictional contact with the vacuum chamber to form an air-tight joint, and means to yieldinglypress saidv closure. rings against the vvacuum chamber,the roll provided with a yielding periphery having at its ends metal closure rings to also bear upon the vacuum chamber and upon the closure rings carried by the other two rolls.

40. In a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable members mounted in the passages in sliding engagement with the Walls 0f said chamber and in` air-tight contact relatively to each other to partially seal said passages, a liquid in contact with parts of the relatively rotating members for further sealing said passages, and fluid operating means cooperating with one or more of said rotatable members adapted to form restricted passages for the passage of a thin film of liquid.

41. In a vacuum drying apparatus, thecombination of a vacuum chamber having passages for the entrance and exit of the material to be treated, sets of three rolls, one set mounted in each of the passages so as to form a closure therefor, one roll of each set having a yielding periphery to firmly press the material to be dried against one of the other rolls of the set and to form a rolling air-tight closure with the remaining other roll, said other rolls having sliding engagement with adjacent portions of the Walls `of the opening, and a sealing liquid to form a thin film of liquid on the one of said other rolls contacting with the material, said film being formed at the place of sliding contact of said roll with the Wall portion, and means to remove the thin film of liquid from the periphery of the roll, before the periphery comes in contact with the material to be dried.

42. A Wiper provided with a contact member formed of yielding material to bear directly upon the surface of a roll and fluid means to press said wiper into contact with the roll to remove liquid from said roll.

43. In a vacuum drying apparatus, the combination of a passage to be sealed,l a passage restricting member adapted to bear directly upon the surface of a roll, means to press it against the roll, and liquid means to act as a lubricant between the passage restricting member and the roll and prevent excessive wear and means to create and maintain a vacuum in the vacuum chamber.

44. The combination with a vacuum chamber having an opening, of means for closing said opening, said means comprising a plurality of rotatable members having air-tight rolling contact one with another in series, the rolling contact surfaces of the extreme members of the series also having sliding engagement throughout their axial extents with adjacent portions of opposite walls respectively of the opening, and the nonrolling surfaces of all the members together having similar sliding engagements with portions defining the remaining Walls of the opening, the members thus cooperating to form a complete closure for the opening, and liquid sealing means for rendering airtight the sliding engagements of the rolling surfaces of the extreme members of the series throughout their axial extents.

45. The combination with a vacuum chamber having an opening, of means for closing said opening, said means comprising a plurality of rotatable members having airtight rolling contact one with another in series, the rolling contact surfaces of the extreme members of the series also having `sliding engagement throughout their axial extents with adjacent portions of opposite Walls respectively of the opening, and the non-rolling surfaces of all the members together having similar sliding engagement with portions defining the remaining Walls of the opening, the members thus cooperating to form a complete closure for the opening, and liquid sealing means for rendering air-tight the sliding engagements of the members of such closure.

46.- The method of sealing an opening in a vacuum chamber Which consists in causing members to move in sliding engagement With the Walls of said chamber and in intimate contact with each other, excluding air from the chamber at certain places by exerting atmospheric pressure and at other places by maintaining a liquid.

47. In a paper web drying machine, the

combination with a feed roll, of an adjustable doctor and a cleaner mechanism coacting with said roll.

48. In a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable meinbers mounted in the passages in sliding eugagement with the Walls of said chamber and in air-tight contact relatively to each other to partially seal said passages, a liquid in contact with parts of the relatively rotating members for further sealing said passages, fluid operating means cooperating with one or more of said rotatable members adapted to form restricted passages for the passage of a thin film of li uid, and means for removing from the sur aces of the rotatable members the liquid which has passed through said restricted passages.

49. In a vacuum drying apparatus, the combination of a vacuum chamber having entrance and exit passages, rotatable members mounted in the passages in sliding engagement with the Walls of said chamber and in airtight Contact relatively to each other to partially seal said passages, a liquid in contact with parts of the relatively rotating members for further sealing said passages, fluid operating means cooperating with one or more of said rotatable members adapted to form restricted passages for the passage of this film of liquid, a Wiper provided with a contact member formed of 10 yielding material to bear directly upon the surface of a rotatable member and fluid means to press said Wiper into Contact with the rotatable member to remove from the surface thereof the liquid which has passed 15 through the restricted passage.

OGDEN MINTON. 

